Spray a casserole dish with oil. Mix all ingredients in a bowl. The mixture needs to hold together but not be too runny or too stiff. I put in 1/2 cup flour which made it a bit stiff so I added a little milk, no more than a tablespoon or two. Cook at 200C for about 1/2 an hour. If you stick a knife in and it comes out clean it’s cooked.